MARSUPIAL MOLE 159 "We may regard as family-characters the pentadaetyle limbs, the existence of three pairs of incisors in the lower and four in the upper jaw; and the tritubercular nature of the upper molars. JSTotoryctes typhlops, the " Marsupial Mole " as it has been termed, was originally discovered by Professor Stirling in Central South Australia. It is a burrowing creature, clothed in a silky fur of a pale golden red, without external ears. It has "been compared in appearance with Chrysochloris, the Cape Golden Mole, and the eminent palaeontologist, Professor Cope, has even insisted upon a real genetic affinity. Edentate affinities have also been suggested, But N'otoryctes has a small pouch opening backwards as in other Folyprotodonts,1 and as it also possesses marsupial bones it must FIG. 88.—Australian Marsupial Mole. Notvryctes typJUops, x £. undoubtedly be referred to the Marsupialia. The animal shows many curious adaptations to its underground mode of life. Certain of the vertebrae in the neck and in the lumbar region are firmly welded together, giving of cotirse a strength of push, and suggesting the Armadillos; the claws of the third and fourth front-toes are greatly enlarged, and must be efficient digging organs. The track of the animal is like that of a rail- way in mountainous country; it burrows for a short distance, emerges, and then descending beneath the surface re-emerges. The red colour of the .fnr is said to be in harmony with the arid soil in which it lives. The native name of the creature is ** Urquamata." It feeds upon ants and other insects. Extinct Polyprotodosits.—Of extinct Polyprotodonts (apart from, those Mesozoic forms which are considered on p. 100) extinct species of Tliylacinus and Dasyurus are known from 1 The male, according to Professor Spencer, lias a rudimentary potieh.